The present invention relates to exhaust gas heat exchangers, as are known in general, and to a sealing device which is suitable particularly for use in the case of exhaust gas heat exchangers.
Exhaust gas heat exchangers are used in exhaust gas recirculation systems in particular for increasing the mass of combusted air taken in during an intake stroke. For this purpose, the density of the recirculating exhaust gas flow has to be increased, which takes place by means of cooling of the recirculated gas flow. This usually takes place by the exhaust gas flow flowing through an exhaust gas heat exchanger where it outputs heat to a coolant, such as a cooling liquid.
Exhaust gas heat exchangers are therefore known, through which both an exhaust gas flow and a coolant flow. The exhaust gas heat exchanger has for the exhaust gas flow connection points for connecting the heat exchanger, with, firstly, an exhaust gas supply line being provided for supplying the hot exhaust gas flow, and an exhaust gas withdrawal line being provided for withdrawing the exhaust gas flow cooled in the exhaust gas heat exchanger. In this case, the exhaust gas flow flows in a throughflow direction through the exhaust gas heat exchanger in a bundle of exhaust gas guiding tubes. The bundle of exhaust gas guiding tubes serves essentially to enlarge the exchange surface between the exhaust gas flow and the coolant flow. At least one coolant supply connection and at least one coolant withdrawal connection are provided for the throughflow of the coolant flow through the exhaust gas heat exchanger. The coolant is guided here in a coolant channel within which it flows around the bundle of exhaust gas guiding tubes.